Effectiveness of closed horizontal drainage when irrigating with «Fregat» sprinkling machine

The restoration and development of irrigation requires the study of the efficiency of closed horizontal drainage in complex natural and economic conditions against the background of wide-reaching irrigation techniques. The purpose of the work is to establish the conditions of operation and efficiency of the systematic closed horizontal drainage on the irrigation arrays of SM "Frigate". The research was conducted on a research and production field, which is located on the Kakhovka irrigated array. The research methodology envisaged the collection and analysis of design and operational characteristics of irrigation and drainage systems, monitoring of data from many years of level of groundwater (LGW) and atmospheric precipitation, the results of periodic drainage surveys and drainage runoff measurements. The assessment of the effectiveness of drainage systems was carried out by comparing the actual and normative (critical) depths of the LGW. With prolonged exposure to LGW above critical depths, the work of drainage was considered insufficient. Prolonged irrigation on the array led to regional and local elevations of the LGW. The regional rise in the background of irrigation occurred at an annual rate of climb of about 0.8 m / year. Local manifestations of flooding and underflooding of land were observed at the bottom of the decline, in the near-channel zones and in the sprinklers machine "Frigate". It was established that at the initial stage of operation of the drainage system closed closures with the greatest depth of lying were included in the work. The consumption of water on collectors reached 2.0-3.8 l / s. Field drains mostly did not have runoff. Closed horizontal drainage under irrigation SM "Frigate" provided high efficiency, reliable water drainage, stabilization of LGW growth and favorable hydrogeological and reclamation situation. According to the results of research, a complex of engineering, technical and technological measures that reduce the water load on drains has been developed. Further development of research should be conducted in the direction of rational use of existing drainage systems, extension of their operation, maintenance and improvement.